Semiconductor device and method of manufacturing the same
View Patent ↗Provided is a semiconductor capacitor including: a capacitor device forming region having a trapezoidal trench which is formed on a surface of a first conductivity type semiconductor substrate; a second conductivity type lower electrode layer provided along the trapezoidal trenches of the capacitor device forming region; a capacitor insulating film formed at least on a surface of the second conductivity type lower electrode layer; and a second conductivity type upper electrode formed on a surface of the capacitor insulating film.
1. A method of manufacturing a semiconductor device, comprising:
forming oxide films by LOCOS on a first conductivity type semiconductor substrate to form thick oxide film regions and thin oxide film regions;
removing the oxide films of the thick oxide film regions and the thin oxide film regions from the first conductivity type semiconductor substrate to form a plurality of trapezoidal trenches;
introducing second conductivity type impurities to a surface of the trapezoidal trenches, to thereby form a lower electrode layer;
forming a capacitor insulating film on the lower electrode layer;
depositing and forming a polycrystalline silicon film, which is formed into an upper electrode, on the capacitor insulating film; and
introducing second conductivity type impurities to the polycrystalline silicon film and patterning the polycrystalline silicon film into a given shape to thereby form the upper electrode.
2. A method of manufacturing a semiconductor device according to claim 1 , wherein the forming a capacitor insulating film comprises forming an oxide film by thermal oxidation.
3. A method of manufacturing a semiconductor device according to claim 1 , wherein the forming a capacitor insulating film comprises forming a silicon nitride film by reduced-pressure CVD.